Medicine balls (also known as exercise balls or fitness balls) have, in one form or another, been used in the exercise, health and fitness fields since ancient times. Animal bladders filled with sand served as medicine balls in Persia over 3000 years ago. In Greece, in the time of Hippocrates, animal skins were sewn up and stuffed with sand to serve as medicine balls. Some of today's medicine balls are made with synthetic outer shell materials, which are then filled with sand, metal shot, other ballast materials, and often lighter filler material, such as yarn, foam, cotton, and the like, to provide a variety of medicine balls having a desired weight, hardness/softness, and size.
Many professional and student athletes, as well as the general public wishing to get into and stay in shape have found exercising with medicine balls to be helpful. Using medicine balls can help develop the abdominal and other core muscles by lifting and moving the medicine ball, for example while performing other exercises, such as doing leg lifts, sit ups, etc., in order to work certain muscles. Medicine balls are also used in rehabilitation of injured athletes.
Medicine balls currently made of various materials, such as leather, vinyl covered nylon, neoprene, polyurethane rubber, plastics, and the like, and are filled with sand, steel shot, and sometimes lighter weight stuffing. For balls that are intended to be bounced, they can be air filled.
Currently, there are medicine balls that incorporate two handles formed into opposite sides of the ball structure which are provided for gripping by users. Some other balls include a rope that passes through a middle of the ball. However, with these prior medicine balls, users are limited as to how they can exercise with the medicine balls. For example, the medicine ball itself is not well adapted to be used as an anchoring device for attachment of accessories, such as elastic straps, pulleys, accessory handles, wrist straps (that would allow hands free use), e.g., with clips and carabiners. Moreover, current medicine balls have not been useful for exercising the legs and other parts of the body due to their lack of engagements and use with other accessories.